import java.util.Enumeration;

import javax.swing.tree.DefaultMutableTreeNode;
public class TreeNode {
	private DefaultMutableTreeNode person;
	private DefaultMutableTreeNode employee;
	private DefaultMutableTreeNode sales_rep;
	private DefaultMutableTreeNode engineer;
	private DefaultMutableTreeNode customer;
	private DefaultMutableTreeNode us_customer;
	private DefaultMutableTreeNode non_us_customer;
	private DefaultMutableTreeNode local_customers;
	private DefaultMutableTreeNode regional_customers;
	
	public static void main(String [] args){
		new TreeNode();
	}
	
	public TreeNode(){
		person = new DefaultMutableTreeNode("Person");
		employee = new DefaultMutableTreeNode("Employee");
		sales_rep = new DefaultMutableTreeNode("Sales_rep");
		engineer = new DefaultMutableTreeNode("Engineer");
		customer = new DefaultMutableTreeNode("Customer");
		us_customer = new DefaultMutableTreeNode("Us_customer");
		non_us_customer = new DefaultMutableTreeNode("Non_us_customer");
		local_customers = new DefaultMutableTreeNode("Local customers");
		regional_customers = new DefaultMutableTreeNode("Regional customers");
		
		person.add(employee);
		person.add(customer);
		
		employee.add(sales_rep);
		employee.add(engineer);
		
		customer.add(us_customer);
		customer.add(non_us_customer);
		
		us_customer.add(local_customers);
		us_customer.add(regional_customers);
		
		Enumeration e = person.breadthFirstEnumeration();
		
		while(e.hasMoreElements()){
		System.out.println(e.nextElement());
		}
	}
}
